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![Fig. 5. 3D Printed Grease Place Brackets [17]](profile/Ashley-Toth-2/publication/360705287/figure/fig5/AS:1182717848891429@1658993317775/3D-Printed-Grease-Place-Brackets-17_Q320.jpg)
Additive manufacturing continues to see increased growth, with adoption in many industrial sectors and increased commercial market value. Market growth is attributed to continued technology and software improvements, growing availability of material types and the ability to produce functional parts with complex geometries. The technology also provi...
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... Jardim, et al., (2021) emphasize that blockchain technology's ability to track and trace company activities is a crucial incentive for implementation while Geroni (2021) highlights its potential for real-time asset tracking and executing smart contracts. Toth, Padayachee, Mahlatji and Vilakazi (2022), reported that the industrial sector's acceptance of new technologies such as the blockchain, centers on factors such as reliability, certainty and economic value associated with the technology for its intended applications. This often prevents innovative advancements from realizing their full potential, primarily due to absences in skills, knowledge, market access, and a comprehensive understanding of the economic advantages the technology could bring (Chua, Wong and Yeong., 2017). ...
Modern supply chains demand adaptability driven by the globalization of production and markets, the fourth industrial revolution (4IR) and recent events such as the unexpected closure of the Suez Canal, the Russia-Ukraine war, and the Covid-19 pandemic. Investing in digital supply chain technologies boosts end-to-end visibility, mitigates risk, and improves the resilience of supply chains. Many disruptive technologies are currently changing the business landscape in Africa. However, Africa has traditionally been an adopter rather than a pioneer of technologies for business development. Although there has been an increase in the use of blockchain technology in various industries, there is still a challenge of understanding how the technology can be applied in the South African rail supply chain context. Thus, it is crucial to investigate how managers perceive the technology and how this understanding affects the decision to use the technology in the rail freight Container Corridor. A gap exists between the understanding, organizational support and benefits of the technology and its application within the corridor. A case study approach was utilized to collect primary data obtained through a structured self-administered survey questionnaire. The main findings of the study were that the understanding of blockchain influenced managers perceptions and willingness to adopt the technology. While the railway operator was committed to implementing blockchain, other operational constraints and inefficiencies still present on the corridor were impediments to further investigation. Furthermore, potential benefits and challenges, costs and resources required as well as the impact on current operations and workings were highlighted by management as important decision-making factors. The study provides valuable insights into disruptive technologies applications within the transport supply chains. It substantiates the significance of how managers view blockchain as a technology to address various challenges as well as enhance operations within the South African freight rail sector.
... The South African heavy haul freight rail company, Transnet Freight Rail, has conducted feasibility studies on additively manufactured railway-related products [8]. These studies have shown that 3D-printing technologies could be used in the railway environment to help to reduce manufacturing costs and lead times for spare part fabrication of legacy-designed systems [8], [9]. ...
... The South African heavy haul freight rail company, Transnet Freight Rail, has conducted feasibility studies on additively manufactured railway-related products [8]. These studies have shown that 3D-printing technologies could be used in the railway environment to help to reduce manufacturing costs and lead times for spare part fabrication of legacy-designed systems [8], [9]. In addition, functional end-use products such as electronic enclosures and replacement parts for track and rolling stock have been created [10], [11], [12]. ...
... Toth et al. [8] presented a case study on designing, manufacturing, and installing a functional 3D-printed roof scoop air vent. The air vent unit was developed as a replacement part for a railway inspection vehicle owing to a shortage of spares. ...
Additive manufacturing continues to see increased growth and adoption across various industries owing to technology improvements and increasing material options. This paper presents a method to optimise the infill structure placement in fused deposition modelling parts. The method uses finite element analysis and the bi-directional evolutionary structural optimisation technique to determine the optimal placement based on stress and validated through testing 3D-printed samples. The results show that multi-infill geometry outperforms traditional rectilinear infill in loading capacity and stiffness. The paper concludes with a real-world application, using this optimisation method on a railway-related part.
... In recent years, the railway industry has started to investigate the use of AM technologies for maintenance purposes ( Ref 4,5). The possibilities also extend toward the use of AM technologies for production of lightweight components ( Ref 6,7). ...
The use of metal additive manufacturing technologies in railways sector can provide increased flexibility in terms of spare part logistics. Combined with lightweight metals such as Al-alloys, the product performance can also be enhanced in terms of weight reduction, vibration and noise control. The railway sector is more likely to exploit large and bulky parts produced by laser powder bed fusion (LPBF), which should have appropriate mechanical properties. Therefore, the whole production chain should be analyzed considering the heat treatment steps suited for a distributed and resource efficient manufacturing scheme. Accordingly, this work analyzes the additive manufacturing of AlSi7Mg alloy by LPBF and its consecutive heat treatment steps. In particular, the impact of LPBF process productivity, heat treatment type and atmosphere composition were considered to analyze the most appropriate route for the needs of the railways applications. The results show that with an appropriate direct aging treatment in air, mechanical characteristics of the alloy could be improved, despite that the high layer thickness used in LPBF could increase process productivity. The absence of a quenching step was found to be favorable for large parts, while the absence of an inert gas such as Ar in the heat treatment did not generate any reduction in the mechanical properties.
... However, despite the several advantages offered by AM technologies, some challenges have been observed over the years from the emergence of AM technologies, namely equipment cost, limited material availability, manufacturing costs, lack of in-house AM resources, limited repeatability or lack of accuracy from build to build, software development and capabilities, limited recyclability, and data storage requirements [4]. Furthermore, the low efficiency of current AM technologies in mass production, limited print bed size, limited AM expertise in the industry, lack of AM standards for different products, and additional post-processing operations can be enumerated as major challenges in this technology [5]. ...
The unique design freedom offered by additive manufacturing (AM) technologies enables engineers to develop more innovative products with relatively lower costs within a shorter period of processing time in comparison with conventional manufacturing methods. On the other hand, the unique capabilities of AM have created a platform for researchers to combine several engineering methods with the new manufacturing technique to grow industrial applications as well as resolve the existing issues with AM processes. Understanding the research values that AM offers academic environments, this paper performs a systematic survey on AM-related research topics in the fields of mechanical engineering and materials science that have attracted much attention from research teams over the last few years. These topics, namely process modelling in AM, innovative research in AM, generative design by AM, material characterisation in AM processes, and finally, design for additive manufacturing (DfAM), are notably investigated through this study.
... industry had limited use of additive materials in railway construction as well as limited design optimization and knowledge of railway engineering standards (Toth et al., 2022). Compared to conventional manufacturing techniques, this technology offers the railway sector advantages in producing complex components for the rail infrastructure and rolling stock environments. ...
To fully harness the economic benefits and regional connectivity across the African continent, a sprout in railway
redevelopment has been witnessed in recent years. However, there is no study showing the challenges, economic
prospects, and knowledge gaps characterizing railway services in Africa. Given that several countries are
redeveloping and planning their railway infrastructure, it is necessary to review the existing literature to identify
research and policy gaps that African railway transportation planners and their development partners need to
take into consideration. Therefore, this systematic literature review analyzed railway-related papers from Africa
to determine the current knowledge of the railway network, challenges, economic prospects, and environmental
sustainability. The review involved 49 peer-reviewed papers published between January 2000 and June 2022 as
well as two recent World Bank reports on railway transportation in Africa. Results showed low penetration of
electric-powered trains, technology integration, and shuttle services. Passenger demand, price optimization,
route scheduling problems, and transport emission experimentation remain knowledge gaps. The impact of
railway projects on wildlife protection and land cover changes would require more empirical studies. The review
showed that past studies excluded reflections on policies, regulation, planning, and the opportunities and
challenges that come with policy interventions. Prospects realization strategies, including railway training fac
tories, regional implementation of standard gauge railway, and proactive regional action plans have been
identified. This study contributes a knowledge map and recommends research gaps that researchers can inves
tigate to strengthen railway management and redevelopment across Africa.
... According to their research, the primary obstacle to technology transfer in host countries J o u r n a l P r e -p r o o f 8 where railway systems are being renovated is a lack of human and financial capital. Trend reports were used by Toth, Padayachee, Mahlatji and Vilakazi [19] to examine the use of additives in railway design, manufacturing, and repair. They found that this use is limited in railway construction, as well as in design optimization and knowledge of railway engineering standards. ...
The long-term sustainability of the railway transportation system is determined by a set of criteria that must be considered. For this reason, multi-criteria decision-making (MCDM) techniques have been used because of their high possibility of providing complementary instruments with successful flexibility. Keeping this in mind, we developed a multi-criteria method to conduct an assessment of currently operational railway systems in West Africa for sustainable transportation based on the examination of key challenges affecting the railway system. This study presents the interval rough step-wise weight assessment ratio analysis-combined compromise solution (IR-SWARA-CoCoSo) model. We have adapted the model to group decision-making by incorporating a new technique for dealing with ambiguity and the utilization of interval rough numbers (IRNs). To evaluate the importance coefficients of criteria in the group decision-making procedure, a new interval rough SWARA method has been introduced as an improvement to handle the issues related to MCDM. For the evaluation of the railway transportation system for sustainable transportation, a novel interval rough CoCoSo method was used. According to the findings, information systems is the most critical challenge to the railway transportation system, while the railway system in Nigeria is the best among others. The results were validated in two stages of sensitivity analysis: a comparison with different interval rough approaches, and the calculation of Spearman's correlation coefficient and WS coefficient for all ranks in the comparative analysis.
As additive manufacturing technology is growing globally, a need exists to better understand the landscape of needs, challenges, and opportunities that enterprises experience to assist policymakers in developing practical and sufficient support policies. This paper draws from the literature on the technology innovation system's innovation indicators to understand the dynamics of South African AM enterprises. From the indicators, we derive a survey instrument that contributes a novel method to analyze innovation systems and a priority tool to identify areas that require priority policy support. In applying the survey instrument, we surveyed forty South African AM enterprises (approximately 80% of the industry) and collected 35 complete responses. The findings show that most AM enterprises are younger than ten years and that value-added enterprises dominate the sector. The enterprises struggle to access support mechanisms for AM technology, and startup enterprises struggle to build appropriate knowledge networks. Based on the priority tool, this paper argues for fourteen policy support opportunities on how AM industries may address their enterprises’ commercialization, knowledge sharing, and supplier challenges
Eklemeli imalat, geleneksel üretim yöntemlerine göre nesnelerin katman katman üretildiği yenilikçi bir yöntemidir. Son yıllarda eklemeli imalatın kullanım alanları hızla artmaktadır. Bu imalat yönteminin birçok sektörde olduğu gibi demiryolu sektöründe de kullanım potansiyeli yüksektir. Demiryolu endüstrisinde eklemeli imalatın genel olarak; demiryolu altyapısında ve demiryolu üstyapısında, demiryolu araçlarında kullanıldığı görülmektedir. Eklemeli imalatın özellikle parçaların özelleştirilmesine olanak tanıması, karmaşık parçaların üretimi ve tasarım özgürlüğü, hızlı prototipleme, malzeme tasarrufu, düşük üretim maliyeti gibi avantajları, demiryolu endüstrisinde ve diğer endüstrilerde kullanımının yaygınlaşmasına olanak sağlamaktadır. Eklemeli imalatın malzeme sınırlamaları ve üretim hızı gibi bazı sınırlamaları olsa da, bu avantajların sunduğu imkanlar birçok alanda yeniliği teşvik etmektedir. Bu çalışmayla, demiryolu endüstrisi ve eklemeli imalat hakkında genel bilgiler verilmiştir. Ayrıca, eklemeli imalatın demiryolu endüstrisinde kullanımı ve kullanıldığı alanlar hakkında inceleme yapılmıştır. Çalışma sonucunda, araştırmacılar için eklemeli imalatın demiryolu endüstrisinde hangi alanlarda kullanıldığı, hangi alanlarda ise kullanımının eksik olduğunun görülmesi ile kullanım alanının geliştirilmesi sağlanmaya çalışılmıştır.
Yük ve yolcu taşımacılığında kullanılan raylı sistem araçlarının (vagon, lokomotif, tren vb.) birlikte hareket edebilmesini sağlayan bağlantı ekipmanlarının genel adı koşum takımıdır. Koşum takımları, araçlara gelen statik yüklerin iletimini sağlamanın yanı sıra elektriksel ve hava bağlantılarının aktarılmasında görevli olup, sistemi oluşturan elemanların tasarımı ve imalatı çeşitli standartlara göre yapılmaktadır. Diğer yandan, lojistik sektöründe daha hızlı ve aynı zamanda güvenli taşımacılık açısından araçları oluşturan tüm parçaların hafifletilmesi önemlidir. Bu çalışmada, minimum ağırlıkta ve yüksek performanslı parçaların tasarımında etkili bir araç olan topoloji optimizasyonu ile koşum takımı elemanlarından üzenginin tasarımı iyileştirilerek ağırlığının azaltılması hedeflenmiştir. Topoloji optimizasyonunda yoğunluk yöntemi olarak da bilinen cezalandırmalı katı izotropik malzeme (SIMP) yönteminden faydalanılmıştır. Öncelikle, standarda uygun olarak modellenen koşum takımı üzengisine 120 kN ve 150 kN yükleme durumları için sonlu elemanlar analizi uygulanmıştır. Daha sonra, topoloji optimizasyonu ile geliştirilen model için aynı şartlarda FEA uygulanarak gerilme dağılımları ve yer değiştirme miktarları karşılaştırılmıştır. Her iki yükleme durumu için en yüksek Von Mises gerilmesi sırasıyla 176,30 MPa ve 220,40 MPa olarak elde edilmiştir. Ayrıca, yeni tasarım üzengiler için en yüksek yer değiştirme miktarları 0,23 mm ve 0,28 mm olarak hesaplanmış olup, bu değerler ilgili standartta belirtilen sınırlar içindedir. Sonuç olarak, topoloji optimizasyonu başarıyla uygulanarak üzenginin kütlesi %9,04 azaltılmıştır. Ayrıca, topoloji optimizasyonu ile geliştirilen model geometrisindeki karmaşıklıktan dolayı üzenginin eklemeli imalat teknolojisiyle üretiminin daha elverişli olduğu kanaatine varılmıştır. Tüm sonuçlar, topoloji optimizasyon metodolojisinin raylı sistem araçlarının ağırlığının azaltılmasında güvenle uygulanabileceğini ve böylece sürdürülebilirliğe önemli katkılar verilebileceğini göstermektedir.
